A small air liquefaction plant by Linde
could be seen at the Bavarian Industrial
and Commercial Exhibition in Nuremberg
as early as 1896. |
The first trial then began in May. In his memoirs, Carl von Linde "Happy and excited, we watched the temperature drop according to the effect described by Thomson and Joule, even after we had far surpassed the limits within which those researchers had worked." Of course the complete cooling process in the 1,300 kilogram apparatus did not happen in one day. And during the night, some of the cold they had obtained was lost again. |
But on the third day, May 29, 1895, a breakthrough: "With clouds rising all around it, the pretty bluish liquid was poured into a large metal bucket. The hourly yield was about three litres. For the first time on such a scale air had been liquefied, and using tools of amazing simplicity compared to what had been used before," said von Linde, still highly enthusiastic even 20 years after that day.
Air liquefaction: just the beginning
Air liquefaction was only the first step for von Linde towards a commercial viable use for his invention. His goal was to separate the liquid air, while re-evaporating it, into its constituents, since only these, primarily oxygen and nitrogen, held promising industrial potential.
First, however, he set about speeding up the long, drawn out process of cooling and liquefaction. To do this, he condensed the air to 200 atmospheres in the compressor and built the countercurrent apparatus out of light, thin copper tubes.